In an interview with Vulture, actor Guy Pearce mentioned that his role in Iron Man 3 isn’t exactly a co-starring effort. When asked about how filming Prometheus and Iron Man 3 differs from The Time Machine, he said:

The main difference was that, when I did The Time Machine, I was pretty much in all of it, so it was a really grueling experience. Prometheus and Iron Man are really kind of cameo stuff, so the experience of shooting them … I mean, on some level, it’s tricky because you feel like a bit of an outsider. You don’t really live the experience that you do when you’re there all day every day with everybody. But at the same time, it can be more fun sometimes because you’re just working in concentrated spurts.

If the amount of screen time he had in Prometheus is an indicator, we can expect him in the Marvel sequel for at least a handful of scenes. Unfortunately, we’ll have to wait until next summer to find out.